HP 8648A, 8648B, 8648C, 8648D User Manual

Operation and Service
Guide

HP
Signal Generator

SERIAL NUMBERS

This manual applies directly to the following HP 8648 model/serial
prefix combinations and below:

HP

HP

HP

HP Part No. 08648-90048
Printed in USA April 1999

Supersedes: November 1998

Notice. The information contained in this document is subject to
change without notice.

Hewlett-Packard makes no warranty of any kind with regard to this
material, including but not limited to, the implied warranties of
merchantability and fitness for a particular purpose. Hewlett-Packard
shall not be liable for errors contained herein or for incidental
or consequential damages in connection with the furnishing,
performance, or use of this material.

Copyright Hewlett-Packard Company 1996, 1998
All Rights Reserved. Reproduction, adaptation, or translation without
prior written permission is prohibited, except as allowed under the
copyright laws.

1400 Fountaingrove Parkway, Santa Rosa, CA 95403-1799, USA

FLEX and Motorola are trademarks of Motorola, Inc.
Windows@ and MS Windows@ are U.S. registered trademarks of
Microsoft Corporation.
Windows NT@ is a U.S. registered trademark of Microsoft

Corporation.

Certification

Hewlett-Packard Company certifies that this product met its published
specifications at the time of shipment from the factory.
Packard further certifies that its calibration measurements are
traceable to the United States National Institute of Standards and
Technology, to the extent allowed by the Institute’s calibration facility,
and to the calibration facilities of other International Standards
Organization members.

Information

Warranty

Regulatory

The regulatory information is in Chapter 4, “Specifications.”

This Hewlett-Packard instrument product is warranted against defects
in material and workmanship for a period of one year from date of
shipment. During the warranty period, Hewlett-Packard Company
will, at its option, either repair or replace products which prove to be
defective.

For warranty service or repair, this product must be returned to a
service facility designated by Hewlett-Packard. Buyer shall prepay
shipping charges to Hewlett-Packard and Hewlett-Packard shall pay
shipping charges to return the product to Buyer. However, Buyer shall
pay all shipping charges, duties, and taxes for products returned to
Hewlett-Packard from another country.

Hewlett-Packard warrants that its software and firmware designated
by Hewlett-Packard for use with an instrument will execute its
programming instructions when properly installed on that instrument.
Hewlett- Packard does not warrant that the operation of the
instrument, or software, or firmware will be uninterrupted or
error-free.

LIMITATION OF WARRANTY

The foregoing warranty shall not apply to defects resulting from
improper or inadequate maintenance by Buyer, Buyer-supplied
software or interfacing, unauthorized modification or misuse,
operation outside of the environmental specifications for the
product, or improper site preparation or maintenance.

NO OTHER WARRANTY IS EXPRESSED OR IMPLIED.
HEWLETT-PACKARD SPECIFICALLY DISCLAIMS THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE.

EXCLUSIVE REMEDIES

THE REMEDIES PROVIDED HEREIN ARE BUYER’S SOLE AND
EXCLUSIVE REMEDIES. HEWLETT-PACKARD SHALL NOT BE
LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT,
TORT, OR ANY OTHER LEGAL THEORY.

. . .

Assistance

maintenance

are available for

Refer

gour

list of

and

and

customer

$br

and

following

O-l. Hewlett-Packard Sales and Service

Hewlett-Packard Company
[phone]

Hewlett-Packard S.A. Hewlett-Packard France
150, Route du Nant-d’Avril 1 Avenue Du Canada
12 17 Meyrin O/Geneva
Switzerland F-91947 Les

(41 22) 780.8111 France

Hewlett-Packard Ltd.

,
England

(44 734) 696622

Hewlett-Packard Company
3495 Deer Creek Road
Palo Alto, California, USA
94304-1316
[phone]

Support

Zone D’Activite De Courtaboeuf 61352 Bad Homburg v.d.H

Cedex

(33 1) 69 82 60 60

Australia

Hewlett-Packard Australia Ltd.
31-41 Joseph Street
Blackburn, Victoria 3130
(61 3) 895-2895 Kirkland, Quebec

OPERATIONS

Hewlett-Packard
Hewlett-Packard Strasse

Germany
(49 6172) 16-O

Hewlett-Packard (Canada) Ltd.

17500 South Service Road

Trans-Canada Highway

2X8
Canada
[phone]

China Hewlett-Packard Company Hewlett-Packard Japan, Ltd.
38

San Huan Xl Road

Shuang

Beijing, China
(86 1) 256-6888

Hewlett-Packard Taiwan
8th Floor, H-P Building
337 Fu Hsing North Road
Taipei, Taiwan
(886 2) 712-0404

Shu Tokyo 192, Japan

Dian District (81 426) 60-2111

9-l

Hachioji

Hewlett-Packard Singapore (Pte.) Ltd.

150 Beach Road
#29-00 Gateway West
Singapore 0718
(65) 291-9088

V

Safety Notes

The following safety notes are used throughout this manual.
Familiarize yourself with each of the notes and its meaning before
operating this instrument.

Caution

Warning

Instrument Markings

Caution denotes a hazard. It calls attention to a procedure that, if
not correctly performed or adhered to, would result in damage to or
destruction of the instrument. Do not proceed beyond a caution sign
until the indicated conditions are fully understood and met.

Warning denotes a hazard. It calls attention to a procedure
which, if not correctly performed or adhered to, could result in
injury or loss of life. Do not proceed beyond a warning note until
the indicated conditions are fully understood and met.

The following markings and caution and warning labels are used on
the instrument. Be sure to observe all cautions and warnings.

!

The instruction documentation symbol. The product is
marked with this symbol when it is necessary for the user
to refer to the instructions in the manual.

The CE93 mark shows compliance with the European
Community 1993 standards.

Warning

Warning
Warning

Caution

The CSA mark is the Canadian Standards Association
safety mark.

“ISMl-A” This is a symbol of an Industrial Scientific and Medical

Group 1 Class A product.

Hazardous voltage always present in this area with instrument

power cord connected to ac line.

Do not remove this screw when removing cover from instrument.

Hazardous Voltage

Hazardous electrical shock. Heat sink is live. Disconnect power
supply before servicing.

vi

General Safety Considerations

Warning

Warning

Warning

Caution

No operator serviceable parts inside. Refer servicing to qualified
personnel.

If this instrument is used in a manner not specified by
Hewlett-Packard Co., the protection provided by the instrument
may be impaired.

For continued protection against fire hazard replace line fuse
only with same type and rating (3 A 250 V type F). The use of
other fuses or material is prohibited.

Always use the three-prong ac power cord supplied with this
instrument. Failure to ensure adequate earth grounding by not using
this cord may cause instrument damage.

prevent electrical shock, do not remove covers.

vii

How to Use This Guide

This guide uses the

following convention:

Documentation

Description

KEY] This represents a key physically located on

the instrument.

Display

This font is used to represent text which
appears on the instrument display.

This guide contains the information required to operate, calibrate, and
repair the signal generator to the assembly level. Included are the
following:

n a quick overview of the signal generator
n examples of typical operation
n a reference section that describes all operation features
n explanations of error messages displayed on the signal generator
n installation instructions

tables of specifications

n tables of post-repair information and recommended equipment

required

n theory of operation of the signal generator
n troubleshooting procedures to identify failed assemblies
n disassembly procedures for removal and replacement of assemblies
n replaceable part numbers
n adjustments required after repair or performance test failure
n performance tests to test the instrument to specifications
n supplemental verification tests to test some unspecified parameters

of the instrument

. . .

Contents

1. Operation

Quick Overview ...................

1. Power Key ...................

2. Display .....................

3. Function and Data Keys

4. Increment Set Keys

5. Knobs. .....................

6. MEMORY
Modulation Source

la. Operation Examples

Getting Started ....................

Operation Examples

Setting the RF Output Signal

Setting the Frequency
Setting the Amplitude
Turn on the RF Output
Setting the Modulation

Incrementing or Decrementing the RF Output Signal

Preliminary Steps ..................

Using the Knob ...................

Using the Increment keys

Using the Memory Registers

Saving Instrument Settings in Register Sequences

Selecting the Sequence
Saving Settings in Registers
Checking the Sequence
Checking a Different Sequence

Deleting a Register from the Sequence

Selecting the Sequence
Deleting a Register

Renumbering the Registers in a Sequence

Decreasing the Register Number
Checking the Sequence

Inserting a Register in a Sequence

Saving a New Register

Offsetting the RF Output from a Reference

Setting the Reference Value
Offsetting the RF Output

Turning the Reference Mode Off or On
Setting a New Reference Value

Holding the Output Attenuator Range

Set the Amplitude Level
Holding the Attenuator
Adjusting the Amplitude

....................

................

................

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. .

...

l-2
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la-l
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la-15
la-16

la-17

la-18
la-18
la-19
la-19
la-20
la-21
la-21
la-21
la-22

Contents-l

Setting a User Selectable Modulated Frequency and

Waveform (Option

or

Only) ........

Setting the Modulation Level ............

Setting the Modulated Waveform ..........

Setting the Modulated Frequency ..........

Signaling a Numeric-Type FLEX Pager (Option

Setting Up Pager Encoding .............

Entering Pager Encoding Settings ..........

Selecting the Format Settings ............

Selecting the Data Rate and Pager Type Settings ...

Selecting the Message Settings ............

Selecting Transmission Repetitions and amplitude . .
Selecting the Pager

(Address) ........

Selecting the Protocol Settings ...........

Selecting the Roaming Mode Settings ........

Encoding ......................

lb. Operation Reference

Frequency and Amplitude ...............

1. Knob ......................

2. Digit-Select Arrow Keys .............

3. REFSET ....................

Units

4. REF

: : : : : : : : : : : : : : : : : :

Function .......................

1. FREQUENCY ..................

2. AMPLITUDE ..................

...................

Setting Up the Pager Encoder .............

1. ENCODER. ...................

Setting the Format .................

FLEX/FLEX-TD

..................

Setting the Data Rate and Pager Type .......

Setting the Message ................

Setting the Encoding Mode ............

Entering the Pager

(Address) .......

Setting the Protocol ...............

Setting the Roaming Mode ............

Message During Encoding .............

Signaling Examples ................

Roaming Example ............

POCSAG

......................

Setting the Data Rate and Pager Type .......

Setting the Message ................

Setting the Encoding Mode ............

Entering the Pager

(Address) .......

Message During Encoding .............

RESYNC.. ....................

Setting the Encoding Mode ............

Message During

..........

.......................

Setting the Data Rate ...............

Message During Encoding .............

SERVICE

......................

Setting the Data Rate . . . . . . . . . . . . . . . lb-35

Only)

la-23
la-23
la-24
la-24
la-25

la-26
la-27
la-27
la-28
la-29
la-29

la-30
la-31
1 a-32
la-32

lb-2
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lb-9

lb-9
lb-12
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lb-16
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lb-19
lb-22
lb-23

lb-25
lb-27
lb-27
lb-29
lb-31
lb-32
lb-32
lb-33
lb-33
lb-33
lb-34
lb-34
lb-34
lb-35

Contents2

Message During Servicing

Pulse Modulation ...................

1. PULSE .....................

Increment Set ....................

1.
START/STOP Encoding
PREV and NEXT

Data .........................

1. MHz/dBm kHz/mV
Units Conversion
ENTER
SHIFT

2. Backspace ....................

3. emf .......................

4.f ........................

Instrument Preset ..................

.....................

.....................

HP-IB

Memory .......................

Modulation Source ..................

RF Output ......................

Rear Panel ......................

Remote Interface (Accessory)

Memory Interface (Accessory)

........................

1. ADRS ......................

2. LOCAL .....................

l.SAV .......................

2. REG ......................

3. Register Recall Arrows

5. DEL ......................

Renumbering the Registers

1. MOD ON/OFF ..................

2.

3. (FREQUENCY) 4. (FREQUENCY/ WAVEFORM)

5. EXTACEXTDC

Setting the Modulation Level

7. MOD INPUT/OUTPUT

1. RF ON/OFF ...................

Vernier Ranges ..................

3. RF OUTPUT ...................

1. 10 MHz REF INPUT and OUTPUT

2. DISPLAY CONTRAST

3. AUXILIARY INTERFACE

4. Line Voltage Connector

5. HP-IB Connector

6.

7. External Pulse Input

1. MOD ON/OFF ..................

2. RF ON/OFF ...................

3. Sequence Selection Arrows

4. Register Recall Arrows

....................

.................

.................

.....................

......................

.....................

kHz

.................

................

.................

ADJ and Language Switches

.............

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...

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lb-35

lb-36

lb-36

lb-38

lb-38

lb-38

lb-38

lb-39

lb-39
lb-39
lb-39
lb-39
lb-40
lb-40
lb-40
lb-41
lb-41
lb-41
lb-45
1 b-45
lb-45
lb-46
lb-47
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lb-48
lb-48

lb-49
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lb-51

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lb-57

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lb-59
1 b-60

Contents-3

1. POWER

2. Copy Arrow Keys

.....................

................

Making a Copy ..................

3.

BUSY

......................

lc. Operation Messages

Front Panel Operation Messages ............

HP-IB

. Command Errors ...............

HP-IB Execution Errors ................

HP-IB Device-Specific Errors .............

HP-IB Query Errors ..................

Service Messages ...................

2. HP-IB Programming

Background .....................

Programming Guidelines ...............

HP-IB Definition ..................

What is Programmable ...............

HP-IB Address ...................

Error Messages ...................

Programming Language ...............

Query .......................

Advanced Programming ...............

Programming Examples ................

Programming RF Frequency .............

Programming RF Frequency and FM Modulation ...

Querying RF Frequency ...............

Programming RF Amplitude .............

Programming Pulse Modulation (Option
Programming Pager Encoder (Option

......

HP-IB Status Reporting ................

External Modulation Input Level Status .......

Example: Check the Condition of Modulation Input

(High or Low) .................

Example: Generate a Service Request for External

Modulation ..................

Reverse Power Protection Status

Example: Check the condition of’the

Unspecified Power (Amplitude) Entry Status .....

Example: Check the Condition of Unspecified Power

Entry .....................

Pager Encoding Status (Option

Only) ......

Example: Check the end of message encoding ...

Example: Check the start of each frame ......

SCPI Command Reference ...............

Subsystem (Option

Only) ........

AM Subsystem ...................

CAL Subsystem ...................

DM Subsystem (Option 1EP Only) ..........

FM Subsystem ...................

Only) ........

Subsystem (Option

Only) ........

PM Subsystem . . . . . . . . . . . . . . . . . . .

.....

lb-60
lb-60
lb-60
lb-61

lc-1

lc-5
lc-7
lc-7
lc-7
lc-8

2-l

2-2
2-2
2-2

2-2

2-2
2-2
2-2

2-2
2-3
2-3
2-3
2-4
2-4
2-4
2-5

2-12

2-14

2-14

2-15
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2-16
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2-17
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2-19

2-20
2-21

2-21

2-22
2-22

2-23

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2-24

2-24
2-25

2-37

Contents-4

Subsystem

PULM Subsystem

Subsystem

Subsystem

.................

..................

.................

.................

Only)

........

Changing Parameters While Encoding (Option
Using the Buffer Memory for the Arbitrary Messages . .
HP-IB Capabilities
HP-IB Connector Information
HP 8656/57 Compatible Language

Program Code Implementation
Receiving the Clear Message
Additional Programming Information

..................

.............

...........

...........

.............

........

3. Installation

Unpacking Your Signal Generator
Connecting AC Power

Power Requirements

Replacing the Fuse

.................

................

.................

Turning On the Signal Generator
Connecting to Other Instruments
Storing the Signal Generator
Shipping the Signal Generator

...........

...........

...........

.............

.............

4. Specifications

Options
Frequency Specifications
Internal Reference Oscillator
output
Spectral Purity
Frequency Modulation
Phase Modulation
Amplitude Modulation
Modulation Source
Remote Programming

Environmental
General
Modulation Generator Option 1 E2
Pulse Modulation Option

Pager Encoder/Signaling Option 1 EP

Frequency
Frequency Modulation
Pager Signaling
Modulation Source
General

Regulatory Information

IS0 9002 Compliant

Statement of Compliance

Noise Declaration

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only)

2-38
2-38
2-39
2-40
2-40
2-41
2-41
2-43
2-44
2-45
2-46
2-48
2-48

3-l
3-2
3-2
3-3
3-5
3-5
3-5
3-6

4-1
4-2
4-2
4-3
4-4
4-5
4-6
4-7
4-8

4-8
4-9
4-9

4-10
4-11

4-11
4-11

4-12

4-12
4-12
4-12
4-13
4-13
4-13
4-13

Contents-5

5. Service

Shipping Your Instrument Back to Hewlett-Packard . . .

Recommended Test Equipment . . . . . . . . . . . .

Post-Repair . . . . . . . . . . . . . . . . . . . . . .

Safety Notes . . . . . . . . . . . . . . . . . . . . .

5a. Theory of Operation

Introduction

Overview
Al Front Panel
A2 Power Supply

A3 Motherboard
A4 Reference
A5 Sig Gen Synth
A6 Output (HP 8648A)
A6 Output (HP
A7 Attenuator (HP 8648A)

.....................

.....................

...................

..................

..................

...................

..................

...............

.............

.............

A10 Frequency Extension (HP
Al 1 Attenuator (HP

...........

Al2 Reverse Power Protection (HP
Al3 Pulse Modulator (HP
Al4 Modulation Generator (Option

Option

.......

A30 Pager Encoder (HP 8648A Option

5b. Troubleshooting Information

Introduction
Troubleshooting Checklist

.....................

...............

AC Mains (line) Fuse Removal .............

Remove the Fuse

................

Modulation Test Points and Power Supply LEDs

Power Supply Distribution ..............

Block Diagrams

....................

5-l
5-2

5-5

5-8

......

....

...

.....

.....

Contents-6

Service Error Messages

6. Replaceable Parts

Introduction . . . . . . . . . . . . . . . . . . . . .

Assembly Replacements . . . . . . . . . . . . . . .

7. Adjustments

Test Equipment ....................

Equipment Setup for Automated Tests
Test Point Extender

.................

........ 7-l

Manual Adjustments .................

Internal Reference Oscillator Adjustment

.......

Pager Encoder Timebase Frequency Adjustment

Automated Adjustments ................

AM Level and Distortion

..............

AM Level .....................

Detector Offset
Output Level
AM Level: FE
Predistortion and Detector Offset
Prelevel

......................

...................

....................

...................

..........

Output Level: Frequency Extension Calibration

...

...

6-l
6-l

7-l

7-2
7-3
7-4

7-6
7-8
7-9

7-11
7-13
7-14
7-15
7-17
7-18
7-19

AM Modulator
Time Base DAC
Motherboard Audio Path

DCFM

.......................

Audio Generator
HF Power Level Accuracy
LF Output Level
LF Power Level Accuracy
FSK Deviation
Filter Path

Service Support Software

Required Test Equipment
Installing the Software
Running the Service Support Software

Starting the Software
Identifying the DUT

...................

...................

..............

..................

..............

..................

..............

...................

.....................

...............

..............

...............

........

...............

...............

Selecting the Performance Test or Adjustments and

the Test. ...................

Defining the Location where the Test Results are

Saved ....................

Running the Tests and Adjustments

........

Reviewing the Test and Adjustment Results
Printing the Test and Adjustment Results
Exiting the Software

Support Software Administration

Software Configuration

The User Configuration

The Administration Configuration
Adding Test Equipment
Removing Test Equipment
Editing Test Equipment

Adding Device Drivers
Removing Device Drivers
Adding Test Drivers
Removing Test Drivers
Adding Datapacks
Removing Datapacks

Motherboard Repair Utility

...............

..........

..............

.............

........

..............

.............

..............

..............

.............

................

..............

................

...............

.............

Reading Information from the A3 Motherboard
Storing Information in the A3 Motherboard

....

......

...

....

7-20
7-22
7-23
7-25
7-26
7-27
7-30
7-31
7-33
7-34
7-35
7-35

7-36

7-42

7-42

7-43

7-44

7-46
7-47
7-47
7-49
7-49
7-50
7-50
7-50
7-50

7-51
7-54
7-55

7-56

7-59

7-60

7-62

7-63

7-65

7-66
7-68
7-70

8. Performance Tests

Calibration Cycle
Required Test Equipment
Performance Test Descriptions

FM Accuracy Performance Test

...................

...............

.............

...........

FM Accuracy Performance Test (Option
FM Distortion Performance Test
AM Accuracy Performance Test

...........

...........

AM Accuracy Performance Test (Option lE2 only)
AM Distortion Performance Test

...........

Phase Modulation Distortion Performance Test
Residual FM Performance Test
Harmonics Performance Test
Spurious Performance Test

............

............

.............

Only)

. .

. .

....

Contents-7

8-l
8-2

8-5
8-6
8-8

8-10

8-12
8-13
8-14

8-15

8-17
8-19
8-20

DC FM Frequency Error Performance Test . . . . . .

RF Level Accuracy Performance Test . . . . . . . . .

Pulse Modulation On/Off Ratio Performance Test

(Option

Only) . . . . . . . . . . . . . . . .

Pulse Modulation Rise Time Performance Test (Option

Only) . . . . . . . . . . . . . . . . . . . .

Pager Encoder Timebase Accuracy Performance Test

(Option 1EP Only) . . . . . . . . . . . . . . . .

FSK Deviation Accuracy Performance Test (Option

Only) . . . . . . . . . . . . . . . . . . . . . .

Internal Timebase: Aging Rate Performance Test

(Option

Only) . . . . . . . . . . . . . . . .

Power Level Accuracy Performance Test (Automated) .

HP 8648A Test Record . . . . . . . . . . . . . . .

HP

Test Record . . . . . . . . . . . . . . .

HP 8648C Test Record . . . . . . . . . . . . . . .

HP 8648D Test Record . . . . . . . . . . . . . . .

9. Supplemental Verification Tests

Required Test Equipment List . . . . . . . . . . . . .

CW Frequency Accuracy Supplemental Verification Test
9 kHz RF Level Accuracy Supplemental Verification Test

Index

8-21

8-22

8-26

8-27

8-29

8-30

8-35
8-38
8-41
8-61

8-85

8-109

9-2
9-3
9-8

Contents-l

Figures

2-l. HP 8648 Status Register Model
2-2. Paging Encoding Status
3-l. Replacing the Fuse

...............

.................

3-2. Power Cable and Mains Plug
4-l. Typical Output Power with Option

HP 8648A Simplified Block Diagram

HP
Fuse Removal

Location Diagram

Simplified Block Diagram

...................

..................

...........

............

.......

.........

.......

Bottom View of Motherboard with Cover Removed . .
HP 8648A Block Diagram
HP

Option

..............

A30 Pager Encoder Block

Diagram ....................

HP 8648A Option

Al4 Modulation Generator Block

Diagram ....................

HP

Block Diagram (1 of 2)
6-l. HP 8648A Replaceable Parts
6-2. HP
6-3. HP

Replaceable Parts

Replaceable Parts

.............

...........

........

Detailed View ..................

7-l.

Test Point Extender
7-2. Timebase Adjust Switch Location
7-3. Internal Reference Oscillator Adjustment Setup

...............

..........

....

7-4. Pager Encoder Timebase Frequency Adjustment Setup
7-5. Variable Capacitor Location
7-6. AM Level and Distortion Test Setup 1
7-7. AM Level and Distortion Test Setup 2
7-8. Location of

531, and

7-9. AM Level Test Setup 1

7-10. AM Level Test Setup 2

7-11. Location of

and
7-12. Detector Offset Test Setup
7-13. Output Level Test Setup
7-14. AM Level: FE Test Setup 1
7-15. AM Level: FE Test Setup 2
7-16. Location of

and
7-17. Predistortion and Detector Offset Test Setup
7-18. Prelevel Test Setup

.................

.............

........

........

on the Motherboard

...............

...............

on the Motherboard

.....

..............

..............

.............

.............

on the Motherboard

.....

.....

7-19. Output Level: Frequency Extension Calibration Test

Setup ......................

7-20. AM Modulator Test Setup
7-21. Location of

on the Motherboard
7-22. Time Base DAC Test Setup
7-23. Motherboard Audio Path Test Setup
7-24. DCFM Test Setup

..................

7-25. Audio Generator Test Setup

..............

.........

.............

.........

.............

. .

2-13
2-18

3-3
3-4
4-3

6-3
6-9

7-3
7-4
7-4
7-6
7-7
7-9

7-9
7-10
7-11
7-11
7-12
7-13
7-14
7-15
7-15
7-16
7-17
7-18

7-19

7-20
7-21
7-22
7-24
7-25
7-26

Contents-9

7-26. HF Power Level Accuracy Test Setup for Power Levels

...................

7-27. HF Power Level Accuracy Test Setup for Power Levels

...............

7-28. HF Power Level Accuracy Test Setup for Power Levels

7-29. HF Power Level Accuracy Test Setup for Power Levels

7-30. LF Output Level Test Setup .............

7-31. LF Power Level Accuracy Test Setup for Power Levels

.................

7-32. LF Power Level Accuracy Test Setup for Power Levels

of<-40dBm .................

7-33. FSK Deviation Test Setup ..............

7-34. Filter Path Test Setup ................

7-35. Welcome Screen ..................

7-36. Important Information Screen ............

7-37. Choose Destination Location Screen .........

7-38. Select Program Folder Screen ............

7-39. Start Copying Files Screen .............

7-40. Installation Status Gauge ..............

7-41. Setup Complete Screen ...............

7-42. Setup Complete Screen ...............

7-43. HP Service Support Program Group .........

7-44. HP Service Software for PC’s Selections .......

7-45. User Information Dialog Box ............

7-46. DUT Selection Dialog Box ..............

7-47. Select Test Equipment and Tests Window .......

7-48. Save As Dialog Box .................

7-49. HP Service Support Software Window ........

7-50. HP Service Support Software Window Displaying Test

Results .....................

7-51. Print the Log File? Dialog Box ...........

7-52. The User Information Window ............

7-53. Test Equipment Drivers in the File Drop-Down Menu .
7-54. Adding Test Equipment Using the Test Equipment Menu
7-55. Adding the Equipment Information Using the New Test

Equipment Window ...............

7-56. Removing and Editing Test Equipment Using the Test

Equipment Window ...............

7-57. The Select Test Equipment and Tests Window ....

7-58. Test Equipment Drivers in the File Drop-Down Menu .
7-59. Adding a Device Driver Using the Test Equipment

Drivers Window .................

7-60. Using the Open Dialog box to Search for a Device

Driver File to Add ................

7-61. Removing a Device Driver Using the Test Equipment

Drivers Window .................

7-62. Test Drivers in the File Drop-Down Menu ......

7-63. Adding a Test Driver Using the Test Drivers Window
7-64. Using the Open Dialog Box to Search for a Test Driver

File to Add ...................

7-65. Removing a Test Driver Using the Test Drivers Window

7-66. Datapacks in the File Drop-Down Menu .......

7-67. Adding a

Using the Datapacks Window . . .

7-27
7-28

7-28
7-29

7-30

7-31

7-32
7-33
7-34
7-36
7-37
7-38
7-38
7-39
7-39
7-40
7-40

7-42
7-42
7-43
7-43
7-44
7-46
7-47

7-47

7-49

7-50

7-51
7-52

7-53

7-54

7-56
7-57

7-57

7-58

7-59

7-60

7-61

.

7-61
7-62

7-63

7-64

Contents-l

7-68. Using the Open Dialog Box to Search for a

File to Add
7-69. Removing a
7-70. 110 Port Error Message
7-71. HP Service Support Program Group

...................

Using the Datapacks Window

...............

.........

7-72. HP Service Software for PC’s Selections .......

7-73. Password Requested by User Information Dialog Box .

7-74. HP8648 Motherboard Repair Utility Window .....

7-75. HP Service Support Program Group

.........

7-76. HP Service Software for PC’s Selections .......

7-77. Password Requested by User Information Dialog Box .

7-78. HP8648 Motherboard Repair Utility Window .....

8-l. FM Accuracy Equipment Setup
8-2. FM Accuracy Equipment Setup for HP
8-3. FM Accuracy Equipment Setup for Option

...........

. .

....

8-4. FM Accuracy Equipment Setup for HP

Option
8-5. FM Distortion Equipment Setup
8-6. FM Distortion Equipment Setup for HP
8-7. AM Accuracy Equipment Setup
8-8. AM Accuracy Equipment Setup for Option
8-9. AM Distortion Equipment Setup

...................

...........

. .

...........

....

...........

8-10. Phase Modulation Distortion Equipment Setup ....

8-11. Phase Modulation Distortion Equipment Setup for HP

...................

8-12. Residual FM Equipment Setup

8-13. Harmonics Equipment Setup

8-14. Spurious Equipment Setup

............

............

.............

8-15. DC FM Frequency Error Equipment Setup ......

8-16. Equipment Setup for the HP 8648A and HP

8-17. Equipment Setup for the HP

..................

> 1300 MHz .

8-18. Pulse Modulation On/Off Ratio Equipment Setup. ...

8-19. Pulse Modulation On/Off

Equipment Setup.

.
8-20. Pager Encoder Timebase Accuracy Equipment Setup .

8-21. FSK Deviation Accuracy Equipment Setup ......

8-22. Internal Timebase: Aging Rate Test Setup ......

8-23. HF Power Level Accuracy Test Setup Setup for Power

Levels > -10 dBm

...............

8-24. HF Power Level Accuracy Test Setup for Power Levels

...............

8-25. HF Power Level Accuracy Test Setup for Power Levels

1300 MHz

...........

8-26. HF Power Level Accuracy Test Setup for Power Levels

...........

1. Frequency Accuracy Equipment Setup

........

9-2. 9 kHz RF Level Accuracy Equipment Setup .....

.

7-64
7-65

7-67

7-68
7-68
7-69
7-69

7-70
7-70
7-71
7-72

8-6
8-7

8-8

8-9

8-10
8-11
8-12
8-13
8-14

8-15

8-16

8-17

8-19
8-20
8-21

8-22

8-23
8-26
8-27

8-29
8-30
8-36

8-38

8-39

8-39

8-40

9-3
9-8

Contents-l 1

O-l. Hewlett-Packard Sales and Service Offices ......

2-1. Programming Command Statements and Descriptions .

2-2. Dictionary of Terms .................

2-3. IEEE 488.2 Capabilities ...............

1. Recommended Test Equipment ...........

5-2. Adjustments and Performance Tests Required after

Repair or Replacement of an HP 8648A Assembly .

5-3. Adjustments and Performance Tests Required after

Repair or Replacement of an HP

Assembly ....................

Al Front Panel (Keyboard) .............

6-l. HP 8648A Replaceable Parts .............

6-2. HP

7-l.

Test Point Extender Parts List ..........

Replaceable Parts ...........

7-2. An Example of Calibration Data for Power Sensors . .

8-l. High Power Level Accuracy Work Table .......

8-2. FSK Deviation Accuracy Work

.........

8-3. HP 8648A Test Record ...............

8-4. HP 8648A Test Record ...............

8-5. FM Accuracy Performance Test ...........

8-6. FM Accuracy Performance Test Option

......

8-7. FM Distortion Performance Test ...........

8-8. AM Accuracy Performance Test ...........

8-9. AM Accuracy Performance Test Option

.....

8-10. AM Distortion Performance Test ...........

8-l 1. Phase Modulation Distortion Performance Test ....

8-12. Residual FM Performance Test ............

8-13. Harmonics Performance Test .............

8-14. Spurious Performance Test .............

8-15. DC FM Frequency Error Performance Test ......

8-16. RF Level Accuracy Performance Test .........

8-17. Pager Encoder Timebase Accuracy Performance Test

(Option

Only) ................

8-18. FSK Deviation Accuracy Performance Test (Option

Only) ......................

8-19. Internal Timebase: Aging Rate Performance Test

(Option

Only) ................

8-20. HP 8648B Test Record ...............

8-21. HP 8648B Test Record ...............

8-22. FM Accuracy Performance Test
8-23. FM Accuracy Performance Test
8-24. FM Accuracy Performance Test Option
8-25. FM Accuracy Performance Test Option
8-26. FM Distortion Performance Test
8-27. FM Distortion Performance Test

Part 1 .......

Part 2 .......

Part 1 . .

Part 2 . .

Part 1 .......

Part 2 .......

8-28. AM Accuracy Performance Test ...........

2-20

2-43

5-2

5-5

5-6

6-5

6-13

7-2
7-53
8-25
8-33
8-41
8-42
8-43
8-44
8-45
8-46
8-48
8-50

8-51
8-51

8-52
8-53
8-54
8-55

8-60

8-60

8-60

8-61
8-62

8-63
8-63
8-64
8-64
8-65
8-65
8-66

Contents-l 2

8-29. AM Accuracy Performance Test Option

8-30. AM Distortion Performance Test . . . . . . . . . . .

8-31. Phase Modulation Distortion Performance Test
8-32. Phase Modulation Distortion Performance Test

8-33. Residual FM Performance Test . . . . . . . . . . . .

8-34. Harmonics Performance Test . . . . . . . . . . . .

8-35. Spurious Performance Test . . . . . . . . . . . . .

8-36. DC FM Frequency Error Performance Test . . . . . .

8-37. RF Level Accuracy Performance Test

8-38. RF Level Accuracy Performance Test

8-39. RF Level Accuracy Performance Test
8-40. RF Level Accuracy Performance Test with Options

. . . . . . . . . . . . . . . .

8-41. RF Level Accuracy Performance Test
8-42. Pulse Modulation On/Off Ratio Performance Test

(Option

8-43. Pulse Modulation Rise Time Performance Test (Option

Only) . . . . . . . . . . . . . . . . . . . .

8-44. Internal Timebase: Aging Rate Performance Test

(Option

8-45. HP 8648C Test Record . . . . . . . . . . . . . . .

8-46. HP 8648C Test Record
8-47. FM Accuracy Performance
8-48. FM Accuracy Performance Test
8-49. FM Accuracy Performance Test Option

8-50. FM Accuracy Performance Test Option

8-51. FM Distortion Performance Test

8-52. FM Distortion Performance Test

8-53. AM Accuracy Performance Test . . . . . . . . . . .

8-54. AM Accuracy Performance Test Option lE2

8-55. AM Distortion Performance Test . . . . . . . . . . .

8-56. Phase Modulation Distortion Performance Test
8-57. Phase Modulation Distortion Performance Test

8-58. Residual FM Performance Test . . . . . . . . . . . .

8-59. Harmonics Performance Test . . . . . . . . . . . .

8-60. Spurious Performance Test . . . . . . . . . . . . .

8-61. DC FM Frequency Error Performance Test . . . . . .

8-62. RF Level Accuracy Performance Test
8-63. RF Level Accuracy Performance Test
8-64. RF Level Accuracy Performance Test
8-65. RF Level Accuracy Performance Test with Options

8-66. RF Level Accuracy Performance Test
8-67. Pulse Modulation On/Off Ratio Performance Test

(Option

8-68. Pulse Modulation Rise Time Performance Test

(Option

8-69. Internal Timebase: Aging Rate Performance Test

(Option lE5 Only) . . . . . . . . . . . . . . . .

8-70. HP 8648D Test Record . . . . . . . . . . . . . . .

8-71. HP 8648D Test Record . . . . . . . . . . . . . . .

8-72. FM Accuracy Performance Test
8-73. FM Accuracy Performance Test
8-74. FM Accuracy Performance Test Option
8-75. FM Accuracy Performance Test Option

Only) . . . . . . . . . . . . . . . .

Only) . . . . . . . . . . . . . . . .

Part 2

. . . . . . . . . . . . . . . .

Only) . . . . . . . . . . . . . . . .

Only) . . . . . . . . . . . . . . . .

Part 1
Part 2

Part 1 . . . . .

Part 2 . . . . .

Part 3 . . . . .

Part 4 . . . . .

‘1

Part 1 . . . . . . .

Part 2 . . . . . . .

Part 1 . . . . .

Part 2 . . . . .

Part 3 . . . . .

Part 4 . . . . .

. . . . .

Part 1
Part 2

. . . . . . .

Part 1 . .

Part 2 . .

. . . . .

Part 1
Part 2

. . . . . . .

. . . . . . .

Part 1 . .
Part 2 . .

8-68
8-70
8-71
8-71
8-71

8-72

8-73
8-74
8-75
8-81
8-81

8-82
8-82

8-82

8-83

8-83

8-85

8-86
8-87
8-87
8-88
8-88
8-89
8-89
8-90
8-92
8-94
8-95

8-95

8-95
8-96
8-97
8-98
8-99

8-105
8-106

8-106
8-107

8-107

8-108

8-108
8-109
8-110
8-111
8-111
8-112
8-112

Contents-13

8-76. FM Distortion Performance Test
8-77. FM Distortion Performance Test
8-78. AM Accuracy Performance Test

Part 1
Part 2

...........

8-79. AM Accuracy Performance Test Option
8-80. AM Distortion Performance Test

...........

8-81. Phase Modulation Distortion Performance Test
8-82. Phase Modulation Distortion Performance Test
8-83. Residual FM Performance Test
8-84. Harmonics Performance Test
8-85. Spurious Performance Test

............

............

.............

8-86. DC FM Frequency Error Performance Test
8-87. RF Level Accuracy Performance Test
8-88. RF Level Accuracy Performance Test
8-89. RF Level Accuracy Performance Test

.......

.......

......

Part 1

Part 2
Part 3

.....

Part 1
Part 2

.....

.....

.....

8-90. RF Level Accuracy Performance Test with Options

................

8-91. RF Level Accuracy Performance Test

Part 4

.....

8-92. Pulse Modulation On/Off Ratio Performance Test

(Option

Only) ................

8-93. Pulse Modulation Rise Time Performance Test

(Option

Only) ................

8-94. Internal Timebase: Aging Rate Performance Test

(Option

Only) ................

1. HP 8648A Frequency Accuracy Supplemental

Verification Test .................

9-2. HP 8648B Frequency Accuracy Supplemental

Verification Test .................

9-3. HP 8648C Frequency Accuracy Supplemental

Verification Test .................

9-4. HP

Frequency Accuracy Supplemental

Verification Test .................

9-5. HP 8648A Option

Supplemental Verification Test

9-6. HP 8648B Option

Supplemental Verification Test

9-7. HP 8648C Option

Supplemental Verification Test

Frequency Accuracy

..........

Frequency Accuracy

..........

Frequency Accuracy

..........

9-8. HP 8648D Option lE5 Frequency Accuracy

Supplemental Verification Test

..........

9-9. HP 8648B 9 kHz RF Level Accuracy Supplemental

Verification Test .................

HP 8648C 9 kHz RF Level Accuracy Supplemental

Verification Test .................

9-l 1. HP 8648D 9 kHz RF Level Accuracy Supplemental

Verification Test .................

8-113
8-114
8-115
8-116

8-117
8-117
8-118
8-118

8-119

8-120

8-121

8-122

8-128

8-129

8-129

8-130

8-131

8-131

8-131

9-4

9-4

9-5

9-5

9-6
9-6

9-7

9-7
9-9

9-9

9-10

Contents-14

Operation

“Operation” contains the following information:

1 Operation Provides a quick overview of the instrument’s

operation.

la Operation

Examples

lb Operation

Reference the instrument’s functions.

lc Operation

Messages HP-IB remote operation messages.

Provides examples to help you learn how to
operate the instrument.

Provides quick access to information about each of

Provides information about both front-panel and

Note

For information about service messages numbered 500 and above,
refer to Chapter

“Service Error Messages.”

Operation l-l

Quick Overview

1. Power Key

2. Display

s

7

8648 Signal Generator

Press

to power up the instrument. The instrument powers up
to the same state it was in when power was turned off, except that
the RF output will be turned off and the digit-select arrow keys

and

will be reset to the least significant digit.

The display can be one of two displays depending on the serial
number prefix of your instrument as illustrated below.

,

AMPUI~E

1-2 Operation

The following table describes the prefixes that apply to the various HP
8648 models equipped with an LCD.

A. Liquid Crystal Display (LCD)

display)

BP 8648A BP 8648B

Prefix Preflx

3636A and below 3623A and below 3623A and below 3613A and below
3643U and below 3642U and below 3642U and below 3642U and below

The display contrast of the LCD can be achieved using the adjustment
that is located on the rear panel of these instruments. Note that this
adjustment is only available for instruments equipped with an LCD.
It allows you to adjust the contrast of the LCD. Turn the adjustment
to optimize the display for viewing from most angles. If the display is
blank, first attempt to adjust the display contrast before returning the
instrument for service.

The following table describes the prefixes that apply to the various HP
8648 models equipped with a VFD.

B. Vacuum Fluorescent Display (VFD)

BP 8648A BP 8648B BP 8648C

Prefix Prefix Prefix Prefix

3836A and above 3836A and above 3836A and above 3836A and above

BP 8648C

Prefix

display)

BP 8648D

Prefix

8648D

3. Function and Data Keys

3836U and above 3836U and above 3836U and above 3836U and above

The VFD is a 2x40 display. The intensity of the this display is at 100

% and cannot be adjusted.

The keys in the FUNCTION and DATA blocks allow you to enter
values for setting the frequency, amplitude, and modulation level of
the RF output signal.

If Option
pager encoder (ENCODER) mode and FM mode.

If Option
mode, the
input alphabetical characters using the DATA and MODULATION
SOURCE blocks when you are in pager encoder mode.

If Option
mode, the
key must be used to store any numeric or alphabetic characters
entered by way of the DATA and MODULATION source blocks.

I

is present, the [FM) (ENCODER) key will toggle between

is present and the signal generator is in the ENCODER

key functions as a SHIFT key. This key lets you

is present and the signal generator is in the ENCODER

key functions as an ENTER key. The ENTER

I

I

Operation 1-3

4. Increment Set Keys

When you press a FUNCTION key, that function becomes the active
function. Press
the active function. Press
function setting by the increment value. (If Option
and the signal generator is in the ENCODER mode, these keys have
alternate functions.)

to view or change the increment value for

or

at any time to change the active

is present

5. Knobs

6. MEMORY

If Option
mode, the
starts or stops any pager encoding activity. In addition, in this mode,
the
move the blinking cursor between each parameter when you are
entering the pager encoding settings.

The knobs are always active when the instrument is in local (front
panel) control. Turn them to increase or decrease the frequency or
amplitude of the RF output. Press
adjust the knob’s resolution.

Press
reference value and turn on the reference mode. Press (REF ON/OFF) to
turn on and off the reference mode without changing the reference
value. When the reference mode is on, the displayed value indicates
the offset between the reference value and the RF output signal.

If Option 1EP is present and the signal generator is in the ENCODER
mode, the AMPLITUDE/ENCODER knob is used to enter a setting for
a pager encoding parameter.

Memory registers allow you to save instrument set-ups and recall
them whenever you wish. Press

number to save the instrument’s current settings.

settings, press
allow you to recall registers in numerical sequence. You can arrange
your registers in up to ten different sequences.

and

is present and the signal generator is in the ENCODER

key functions as a START/STOP key. This key

function as PREV and NEXT keys. These keys let you

or

next to each knob, to set the displayed value as the

and enter a two-digit register

and enter the register number. The arrow keys

next to each knob, to

recall the

1-4 Operation

The number of the currently selected sequence and the last register
selected are always displayed in the lower-left corner of the display to
help you keep track of where you are in your testing process.
(If Option
on any pager encoding menu.) The memory register examples
provided in Chapter la, “Operation Examples,” show you how
to create a sequence and how to delete or add registers in your
sequence.

is present, the sequence and register are not displayed

7. Modulation Source

Press

ON/OFF) to turn on or off the modulation source. Press

or

to select one of the internal source tones

for modulating the RF output signal. These tones are also available

as an output signal at the MOD INPUT/OUTPUT port when they are

selected. Press

or

to ac- or dc-couple an external

audio source via the MOD INPUT/OUTPUT port.
Press

+ EXT

to frequency modulate the RF signal with

the internal 1 kHz tone and an external source at the same time.
(Additional internal plus external modulation capabilities are available
for HP-IB operation.)

+ EXT

will also amplitude or phase

modulate the RF signal with the internal 1 kHz tone but it will not be
dc-coupled.

If Option 1EP is present, the
Option

is present, the

(FREQUENCY) key, or if

(FREQUENCY/WAVEFORM)
key scrolls between five states: a fixed 1 kHz internal source and a
variable-frequency internal source with four different waveform
selections. The four modulation waveforms are sine, triangle, square,
and sawtooth (or ramp).

Operation

Operation Examples

This section contains operating examples to help you learn how to
operate the signal generator. These examples can be performed
without any additional equipment. The pager testing example can
only be performed if Option 1EP is present.

Getting Started

If this is the first time you have operated this instrument, perform
each of the following examples for a quick introduction to general
operation. After you have completed the examples, try operating the
instrument’s remaining functions on your own. If you have trouble
or want additional information on a function, refer to Chapter lb,

“Operation Reference.” If a message is displayed that you do not

understand, refer to Chapter lc, “Operation Messages.”

Operation Examples la-l

Operation Examples

This section provides the following examples of signal generator

operation. The item numbers of the operation examples correspond to

the numbers called out on drawing of the instrument front panel.

1. Setting the RF Output Signal

2. Incrementing or Decrementing the RF Output Signal

3. Using the Memory Registers

4. Offsetting the RF Output from a Reference

5. Holding the Output Attenuator Range

6. Setting a User Selectable Modulated
(Option

or

Only)

7. Signaling a Numeric-Type FLEX Pager (Option

RF

A

and Waveform

Only)

la-2 Operation Examples

Setting the RF Output Signal

In this example, you will set the frequency, amplitude, and modulation
level of the RF output signal.

Setting the Frequency

Setting the Amplitude

1. Set the frequency to 100 MHz using the keys shown below the
instrument diagram.

If you make a mistake while entering a value, press

to correct

it.

FREQUENCY

100.00000 MHz

2. Set the amplitude to -100 dBm.

Operation Examples la-3

Turn on the RF Output

3. Press

to turn on the RF output.

RF OFF is displayed below the amplitude setting when the RF

output is turned off.

Setting the

Modulation

4. Set the FM deviation to 3 kHz.
The modulation rate is displayed below the deviation setting. Use

the MODULATION SOURCE keys to select a modulation source and
turn modulation on or off.

FREQUENCY

100.00000 MHz

MODULATION

FM 3.00

AMPLITUDE

-100.0 dBm

,

la-4 Operation Examples

Incrementing or Decrementing the RF Output Signal

In this example, you will increment the amplitude and frequency of
the RF output signal.

Preliminary Steps

Using the Knob

1. If they are not already set, set the frequency to 100 MHz, and the
amplitude to -100 dBm.

FREQUENCY

100.00000 MHz

2. Increment the amplitude using the knob.
Press

or

when you wish to adjust the increment resolution.

MODULATION

AMPLITUDE

-100.0

.dnv

Operation Examples la-5

Using the Increment

keys

3. Enter a frequency increment of 25 kHz.
The $ symbol is displayed when you press

that the displayed value is the increment set value.

-101.0

4. Increment the RF output frequency in 25 kHz steps.
The increment keys affect the last FUNCTION selected

(FREQUENCY, AMPLITUDE, FM, AM or

to indicate

000

0

0 00

q c

0 q OCI

FREQUENCY

100.02500 MHz

MODULATION

-101 .O dBm

la-6 Operation Examples

Using the Memory Registers

The memory register examples show you how to create a sequence of

registers, delete a register from that sequence, renumber the registers
in the sequence, and insert a new register in the sequence.

Up to 10 register sequences can be defined (0 through 9). A sequence
can contain up to 100 registers (00 through 99). There are a total of
300 registers available in the instrument. The registers can be used

in the sequences in any combination (such as 10 sequences of 30

registers each, or 3 sequences of 100 registers each) as long as the
total does not exceed 300 registers. It is not possible to have all 10
sequences each contain 100 registers as that would be 1000 registers.

(If Option

is present, there are a total of 70 registers available.)

SEQ 0

SEQ

9

\

FM

REG 00

99

36.0dBm
RFOFF

Operation Examples la-7

Saving Instrument

Settings in Register

Sequences

In this ten step example, you will use the memory keys to create

a sequence containing three registers. Each register will contain a
different frequency setting.

Selecting the Sequence

1. Select sequence 0.
If there are registers saved in sequence 0, the message shown

in the display below will not appear. Note that the steps in this
example will cause the settings in registers 00, 01, and 02 of

sequence 0 to be changed.

.dnv

Saving Settings in Registers

2. Set the frequency to 10 MHz.

3. Save the instrument settings in register 00.

FREQUENCY

10.00000 MHz

SEQ 0 REG 00

MODUIATION

,

la-8 Operation Examples

4. Set the frequency setting to 11 MHz.

MODULATION

5. Save the instrument settings in register 01.

6. Set the frequency to 12 MHz.

Operation Examples la-9

7. Save the instrument settings in register 02.

FREQUENCY

12.00000 MHz

SEQ 0 REG 02

Checking the Sequence

8. Recall the registers in sequence 0.
The

which key was pressed last

and

FREQUENCY

SEQ 0 REG 01

keys recall registers or sequences depending on

12.00000 MHz
SEQ 0 REG 02

10.00000 MHz

SEQ 0 REG 00

MODULATION

or

MODULATION

AMPLITUDE

AMPLITUDE

la-l 0

Operation Examples

Checking a

9. Select sequence 1.

SEQ

Sequence

FREQUENCY

MODULATION

10. Step through the registers in sequence 1 if there are registers
saved in it.

Note

Sequence 1 does not contain the settings you saved in sequence

0. The instrument enables you to save different settings in each
sequence to create up to ten different sequences for your testing.
Remember when you save or recall a register, be sure that the correct
sequence is also selected.

Operation Examples

la-l 1

Deleting a Register

from the Sequence

In this example, you will delete a register from the sequence you
created in the preceding example.

Selecting the Sequence

1. Select sequence 0.

Note

FREQUENCY

SEQ 0

MODULATION

AMPLITUDE

Deleting a Register

2. Delete register 01 from sequence 0.
The contents of the register are recalled when it is deleted. This

allows you to resave the contents if you need to.

FREQUENCY

11 .OOOOO MHz
SEQ 0 REG --

MODULATION

AMPLITUDE

,

la-12 Operation Examples

delregl

Step through the remaining registers in sequence 0.

3.
The deleted register number has been removed from the sequence.

Note that the instrument does not renumber the registers when
one is deleted.

12.00000 MHz

SEQ 0 REG 02

10.00000 MHz
0 REG 00

MODULATION

AMPUTUDE

Operation Examples la-13

Renumbering the

Registers in a

Sequence

In this example, you will eliminate the skip from register 00 to register
02 in sequence 0 caused when you deleted register 01 in the previous
example.

Decreasing the Register Number

1. Delete register 02.
The settings saved in register 02 are recalled when it is deleted.

2. Save the settings from register 02 into register 01.

12.00000 MHz

SEQ 0 REG 01

la-14 Operation Examples

Checking the Sequence

3. Step through the register sequence.

Note

In this example, you renumbered one register. When you need to
renumber two or more registers, use

each register until you get to the last register in the sequence, then

use (DEL).

12.00000

MHz

instead of (DEL) to recall

I

Operation Examples la-15

Inserting a Register in

a Sequence

In this example, you will insert a register into the sequence you
created in the previous example. The process involves incrementing
each register number that comes after the point in the sequence
where you wish to insert a register.

1. Recall the last register in sequence 0.

FREQUENCY

12.00000 MHz

SEQ 0 REG 01

MODULATION

AMPUTUDE

2. Save the recalled settings into register 02.

Operation Examples

la-l 6

3. Recall register 00.
Register 01 can now be used to save the settings that are saved in

register 00.

FREQUENCY

MODULATION

,

4. Save the recalled settings into register 01.
Register 00 can now be used to save the new settings.

FREQUENCY

10.00000 MHz

SEQ 0 REG 01

Saving a New Register

5. Set the frequency to 8 MHz.

FREQUENCY

8.00000 MHz

I

6. Save the settings in register 00.

MODULATION

MODULATION

AMPUTUDE

,

I

Press

to check the new sequence.

8.00000 MHz

Operation Examples

la-l 7

Offsetting the RF Output from a Reference

In this example, you will enter an RF output frequency, set it as the
reference value, and then offset the RF output frequency 10 MHz
below the reference value.

Setting the

Reference

Value

1. Set the frequency to 500 MHz.

500.00000 MHz

2. Set 500 MHz as the reference frequency.
The A symbol appears in the display to indicate that the reference

mode is selected. The output frequency is still 500 MHz.

la-l 6

Operation Examples

Offsetting the RF

output

3. Offset the output frequency 10 MHz below the reference
frequency.

You can enter in the offset value directly, or use the knob or
and

keys.

FREQUENCY

-10.00000

MODULATION

AMPLITUDE

Attention!

In the reference mode, the output frequency equals the reference
frequency

Turning

4. Turn off the reference mode to display the actual output
frequency.

5. Turn on the reference mode without changing the reference
frequency.

the displayed offset frequency.

the Reference Mode Off or On

FREQUENCY

490.00000

MHz

MODULATION

AMPLITUDE

-------

.

I

Operation Examples la-19

6. Change the displayed units to
Note that for amplitude, reference settings are displayed in

units only.

FREQUENCY

MODULATION

Setting a New Reference Value

7. Set the current output frequency as the new reference frequency
at any time.

la-20 Operation Examples

Holding the Output Attenuator Range

In this example, you will hold the output attenuator so it does not

change ranges when you change the amplitude setting. This will

prevent attenuator range changes from affecting the output signal.

Set the Amplitude

Level

Holding the

Attenuator

1. Set the amplitude level to -82 dBm.

2. Hold the attenuator at this setting.

MODULATION

-82.0

AMPLITUDE

-82.0
HOLD

Operation Examples la-21

Adjusting the

Amplitude

3. Adjust the amplitude setting.
Now amplitude changes do not cause the attenuator to change its

range setting. Consequently, amplitude changes are limited to the
range provided by the instrument’s vernier. For information about
the instrument’s vernier ranges, refer to Chapter lb, “Operation
Reference.

la-22 Operation Examples

Setting a User
Selectable

Modulated

Frequency and

Waveform

(Option lE2 or

Note

Setting the

Modulation Level

This modulation example can only be performed if Option
is present.

In this example, you will select the modulation level and the
modulated frequency and waveform of the RF signal output.

1. Select FM modulation with a deviation of 25 kHz.
Either LAM) or

The modulation type (FM, AM, or
(deviation or depth) is displayed on the top line of the front-panel
display as shown.

modulation may be used instead of (FM.

and the modulation level

or

Operation Examples la-23

Setting the Modulated

Waveform

(Frequency/

Waveform)

2. Press the

(FREQUENCY/WAVEFORM) key until

selected.
Repetitively pressing the

(FREQUENCY/WAVEFORM) key

selects one of five states:

n A fixed 1 kHz sine-wave internal source.
n A variable-frequency sine-wave source

(indicated by SIN preceded by the frequency value).

n A variable-frequency triangle source (TRI).
n A variable-frequency square-wave source
n A variable-frequency sawtooth (or ramp) source (SAW).

is

Setting the Modulated

Frequency

3. Set the modulated frequency to 1.5 kHz.
The

key is the only accepted units key.

la-24 Operation Examples

Signaling a
Numeric-Type
FLEX Pager

(Option

Only)

In this example, you will set up the pager encoder to send a signal
appropriate to test a numeric-type FLEX pager.

Note

This pager encoding example can only be performed if Option
present.

The front panel of the Option 1EP instrument is different from the
standard instrument’s front panel. The green and blue labels are
incorporated for the pager encoding mode only. Therefore, these keys
have multiple functions on instruments with Option

FORMAT FLEX
POLARITY NORMAL

FILTER ON

is

HP 8648A Option

Signal Generator

Operation Examples la-25

Setting Up Pager

Encoding

The following steps are required to set up pager encoding on the

signal generator. Details of setting each parameter are provided
following this overview.

1. Before entering the signal generator pager encoder mode,
set the correct carrier frequency and FM deviation for the
pager-under-test. (The FM deviation is 4.8 kHz for FLEX and is

4.5

for POCSAG.)

2. Press
below the amplitude setting when the RF output is turned off.)

3. Enter the pager encoder mode by pressing

wasn’t the last active function, press (FM) (ENCODER) twice.

4. Set up the pager encoder parameters to meet the test requirements

of your specific pager.

Use the
encoder parameters. The cursor will blink around the first letter
of the active parameter. The
sequentially through each pager encoder parameter and the

(PREV) ke

To move between settings for each parameter, rotate the
AMPLITUDE/ENCODER knob until the desired setting is
displayed. When characters are entered by way of the keypad
(such as the capcode), terminate the entry with the
(ENTER) key.

5. Start signaling the pager after all of the encoder parameters are set
by pressing the

to turn on the RF output. (RF OFF is displayed

(ENCODER). If FM

(NEXT) and

y moves backward sequentially.

(PREV) keys to scroll through the

(NEXT) key moves forward

(START/STOP) key.

la-26 Operation Examples

Entering Pager

Encoding Settings

1. Display the first pager encoder menu.
After setting your pager’s carrier frequency and an FM deviation

of 4.8 kHz (for a FLEX pager) on the signal generator, press the

(ENCODER) key once again to display the first pager encoder

menu (FORMAT). The

(ENCODER) key toggles between the

frequency modulation menu and the pager encoder menu.

Selecting the Format

Settings

FORMAT

POLARITY

MODmION

FLEX

NORMAL

FILTER ON

2. Set FORMAT to FLEX, POLARITY to NORMAL, and FILTER to ON.
a. With the blinking cursor on the “F” of FORMAT, set the FLEX

format by rotating the AMPLITUDE/ENCODER knob until FLEX
is displayed.

b. Press the

(NEXT) key to move the blinking cursor to
POLARITY, then use the AMPLITUDE/ENCODER knob to set
the polarity to NORMAL.

c. Using the

(NEXT) key and the AMPLITUDE/ENCODER

knob, set FILTER to ON.

FORMAT
POLARITY

FLEX
NORMAL

FILTER ON

Press the

(NEXT) key to move to the next page.

Operation Examples la-27

Selecting the Data

Rate and Pager Type

Settings

3. Set DATA RATE to
AMPLITUDE/ENCODER knob and the

and PAGER TYPE to NUMERIC, using the

(NEXT) key.

You may choose to set the data rate to one of the other settings;

your FLEX pager should automatically adjust.

1

Press the

DATA RATE
PAGER TYPE NUMERIC

(NEXT) key to move to the next page.

4. Set VECTOR TYPE to STANDARD using the AMPLITUDE/ENCODER
knob.

STANDARD

la-28 Operation Examples

Press the

(NEXT) key to move to the next page.

Selecting the Message

Settings

5. You may choose one of the five fixed messages (only numbers one
and five are useful for numeric pagers) or you may define your
own message. For this example, use your own phone number as
the user-defined message:

a. Set MESSAGE NO. to 6 and MESSAGE LENGTH to 40 using the

AMPLITUDE/ENCODER knob and the

(NEXT) key.

Selecting

Transmission

Repetitions and

amplitude

b. Press the

(NEXT) key again to select the FREE MESSAGE

parameter.

c. Enter your phone number with the numeric keys and

terminate your entry with the

MESSAGELENGTH 40

Press the

MESSAGE NO.6

(NEXT) key to move to the next page.

6. Set MODE to SINGLE and AMPLITUDE to 0.
AMPLITUDE/ENCODER knob and the

(ENTER) key.

using the

(NEXT) key. Enter
the numeric values using the numeric keys and the
(ENTER) key.

Press the NEXT

key to move to the next page.

Operation Examples la-29

7. Set IMMEDIATE STOP to OFF, HEADER to ON, and TERMINATOR to
ON using AMPLITUDE/ENCODER knob and the

These are default settings that normally would not be adjusted.

(NEXT) key.

Selecting the Pager

(Address)

Note

IMMEDIATE STOP OFF
HEADER ON

Press the

8. Enter your pager’s
menu. The
alphabetical characters. For example, to enter the following

Th

AMPLITUDE/ENCODER knob, set DUMMY CALL to OFF.

The pager’s
parameters of the last two menus.

(NEXT) key to move to the next page.

A0012477, press

(ENTER).

contains information that automatically sets the

(address) in the pager code

(SHIFT) key is required to enter

(SHIFT),

en, using the

TERMINATOR ON

(A), @i?ZV),

(NEXT) key and the

la-30 Operation Examples

Press the

(NEXT) key to move to the next page.

9. ADDRESS TYPE and ADDRESS1 are set automatically when the
is entered in the previous menu. If A0012477 was

entered, SHORT and 0045245 would be displayed respectively.
Generally, you would not change these settings.

Selecting the Protocol

Settings

Note

Press the

10. FRAME, PHASE, and COLLAPSE CYCLE are also set automatically
when you enter the pager’s
previously, 0 11, D, and 4 would be displayed.

If MODE is set to BURST or CONT instead of SINGLE, you may choose
to change the collapse cycle to 0 to 7. With a collapse cycle of 4,
the pager will receive the message once every 16 frames
collapse is 0 or 1, the pager will receive the message either every
frame (2’), or every other frame (2l).

Press the

(NEXT) key to move to the next page.

If you entered A0012477

If the

(NEXT) key to move to the next page.

Operation Examples

la-3 1

Selecting the Roaming

Mode Settings

11. Set ROAMING MODE to NONE using the AMPLITUDE/ENCODER
knob.

Encoding

Press the @j (NEXT) key to move to the next menu.

12. To start encoding after selecting all pager encoder parameters,
press the

(START/STOP) key.

la-32 Operation Examples

Operation Reference

This chapter describes each of the instrument’s functions including all
of the front panel keys, the rear panel connectors, and the optional
remote interface and memory interface. This information is presented
in the same functional groups as the front panel key functional
groupings.

Note

Option
Consequently the front panel of the Option
different from the standard instrument’s front panel. The green and

blue labels are incorporated for the pager encoding settings only.

Therefore these keys have multiple functions on instruments with
Option

adds a pager encoder capability to the standard functions.

instrument is

Operation Reference

1 b-l

Frequency/Amplitude

Frequency and Amplitude

1. Knob

2. Digit-Select Arrow Keys

Note

The knob and reference set keys work similarly for both frequency
and amplitude settings.

Turn the knobs to increment or decrement the frequency and
amplitude settings. The knobs are always active when the instrument
is in local operation.

If Option 1EP is present and the signal generator is in the ENCODER
mode, the knob in the AMPLITUDE/ENCODER block is used to select
the desired setting for each pager encoder parameter.

Press these digit-select arrow keys
changed with the knob.

The knobs increment the selected digit only. For information about
incrementing by an arbitrary value using the increment set keys, see

“Increment Set” in this chapter.

to select the digit to be

Operation Reference

1 b-2

Frequency/Amplitude

3. REF SET

4. REF ON/OFF

Output Power

Trouble?

Press
RF output setting as the reference value. The reference value
is stored in non-volatile memory until you replace it by pressing

When you press
value and the units. When
the offset between the reference value and the RF output signal.

The RF output signal is not changed when you press this key.

to turn on the reference mode and to set the current

again.

the

symbol is displayed between the

appears, the displayed value indicates

Units

When you press
or kHz. For amplitude, values can be entered in any of the amplitude
units provided, but they are displayed in dB only.

Press (REF ON/OFF] to turn off the reference mode if it is on, or to turn
on the reference mode without changing the reference value.

When you turn on the reference mode, the displayed value indicates
the offset between the reference value and the current RF output
setting.

The RF output signal is not changed when you press this key.
If the RF output power seems too low, look for

between the power level value and the
that reference mode is turned on. The displayed value is not the

output power level; it is the offset between the reference value and
the output power. To exit the reference mode, press
can then reset the output power to the desired level.

for frequency, values can be entered in MHz

in the display

indicator. The

tells you

ON/OFF].

Operation Reference

1 b-3

Function

Function

1. FREQUENCY

The RF output frequency range for each model is shown in the
following table. When making frequency changes, the instrument does
not turn off the RF output. However, the power does blank for a few
milliseconds when crossing the frequencies at 249, 501, 1001, 1260,

1600, 2001, 2520, and 3200 MHz.

Frequency Ranges

HP 8648A
HP 8648B

HP 8648C

HP

9 kHzto2000 MHz
9
9

1000 MHz

3200 MHz
4000 MHz

Frequency switching typically takes less than 75 ms at frequencies
lower than 1001 MHz, and less than 100 ms at higher frequencies.

1 b-4

Operation Reference

Function

2. AMPLITUDE

3. FM
AM

The RF output amplitude range is shown in the following table. When
making amplitude changes, the instrument does not turn off the RF
output. The period of any over- or under-ranging that may occur
during level transitions is typically less than 30 ms.

Output Amplitude Ranges

Press

HP 8648A

HP 8648BICID

HP

with Option

to set the peak deviation for frequency modulation. Then

to 1000 MHz

MHz

MHz

< 100

1000 MHz
1500 MHz
2100 MHz

MHz

MHz

to

136
+13to
+
+17to136
+20to
+19to136
+17to136
+15to136
+13to136

136

to

136

136

use the data entry keys to enter the desired value of deviation. The

values allowed depend on the RF frequency selected. See Chapter 4,

“Specifications” for peak deviation specifications.

Press (AM) to set the amplitude modulation range. Then use the data
entry keys to set the desired value of range. Values from 0 through

100% are allowed.

Press

to set the peak deviation for phase modulation. Then use

the data entry keys to enter the desired value of deviation. The

values allowed depend on the RF frequency selected. See Chapter 4,

“Specifications” for peak deviation specifications.

Operation Reference

1 b-5

Function

Setting Up the

Pager Encoder

Note

The pager encoder mode is available only on instruments with
Option

Option
functions. Consequently the front panel of the Option
is different from the standard instrument’s front panel. The green
and blue labels are incorporated for the pager encoding settings only.
Therefore these keys have multiple functions on instruments with
Option

FORMAT FLEX
POLARITY NORMAL FILTER ON

adds pager encoding/signaling capabilities to the standard

instrument

Operation Reference

1 b-6

HP 8648A Option

For numeric messages, the following keys are assigned for the special
characters in addition to the standard numeric keys (0 to 9).

Signal Generator

Front

Panel Key

S

S

UU UU

Space

Space SpaceSpace

Character B3 B2

(Hyphen)(Hyphen)

SpareSpare

BO

1 0 1 01 0 1 0
1 0 1 11 0 1 1
1 1 0 01 1 0 0
1 1 0 11 1 0 1
11101110
11111111

1'

1. ENCODER

Function

Note

Before selecting the pager encoder mode check that the correct pager
carrier frequency and FM deviation have been set.

To select the pager encoder mode, press

(ENCODER) twice:
once to set FM deviation, then again to toggle between the standard
functions and the pager encoder mode. The display will look like the
following:

FORMAT

POLARITY

FLEX
NORMAL FILTER ON

This format menu is always displayed first when the pager encoder

mode is selected.
The

(PREV) and

(NEXT) keys are used to move the blinking

cursor between each parameter.
The knob in the AMPLITUDE/ENCODER block is used to select the

desired setting for each pager encoder parameter.
To start or stop encoding, press

(START/STOP).

Operation Reference

1 b-7

Function

Setting the Format

Note

The format menu, shown in the previous figure, has the following

settings:

n FORMAT selects the pager protocol being tested.

FLEX:
FLEX-TD:
POCSAG:
PN15:
RESYNC:

FLEX format
FLEX-TD format

POCSAG format
Pseudorandom Sequence (PN 15)
Re-synchronization function (for FLEX/FLEX-TD
pagers only)

SERVICE:

Servicing the HP 8648A Option

Depending on the format selected, the parameter menus will be
different. Messages displayed while sending encoding signals are also
unique to each selection.

n POLARITY selects the data polarity.

NORMAL:

“1”: Carrier

“0”: Carrier + Deviation

Normal polarity

Deviation

“1”: Carrier

Carrier

Deviation “10”: Carrier

“11”: Carrier + (Deviation/J)
“01”: Carrier

Deviation “00”: Carrier

Deviation

Deviation

INVERSE:

“1”: Carrier + Deviation “1”: Carrier

“0”: Carrier

n FILTER selects whether or not the baseband modulation filter

Inverse polarity

Deviation “10”: Carrier

Deviation

Carrier + Deviation

Bessel low-pass filter, -3

Deviation
“11”: Carrier
“01”: Carrier + (Deviation/S)

at 3.9

(Deviation/J)

is used.

Normally the filter is on.
ON:

OFF:

Uses the low-pass filter
Does not use the low-pass filter

lb-6 Operation Reference

FLEX/FLEX-TD

Function

Setting the Data Rate and Pager Type

The parameter menu for the data rate and the pager type looks like

the following:

MODULATION

DATA RATE

PAGER TYPE NUMERIC

n DATA RATE specifies how fast the data stream is output in bits per

second and whether it is 2-level or 4-level FSK.

1600 bps, 2-level FSK
3200 bps, 2-level FSK
3200 bps, 4-level FSK
6400 bps, 4-level FSK

n PAGER TYPE specifies the type of message a pager under test can

respond to and is selectable from the following:
TONE ONLY:

NUMERIC:
ALPHANUMERIC:
HEX/BIN:

Short Message/Tone only type
Numeric type
Alphanumeric type
HEX/Binary type

Operation Reference lb-9

Function

q If NUMERIC is selected, the next setting to be selected is VECTOR

TYPE as shown:

TYPE

n VECTOR TYPE identifies the type of message as follows:

STANDARD:

The pager-under-test displays the numeric

STANDARD

message it receives.

SPECIAL:

The pager-under-test converts the numeric
message to a pre-defined message which is
displayed.

NUMBERED:

The message numbers are assigned for each
paging address separately starting at 0
and progressing up to a maximum of 63 in
consecutive order.

If NUMBERED is selected, the next parameter to be selected is

NUMBER as follows:

lb-10 Operation Reference

encode21

NUMBER is for setting the initial number of the numbered
numeric message that will be transmitted. The allowable range
is 0 to 63.

q

If HEX/BIN

LENGTH:

is selected, the next setting to be selected is

BLOCKING

Function

Note

BLOCKING LENGTH

I

n

BLOCKING LENGTH

indicates the bits per character as follows:

1 bit per character

7BITS:
8BITS:

14BITS:

7 bits per character
8 bits per character

14 bits per character
16 bits per character

Enter the message in the hexadecimal format to the MESSAGE
NO. 6 in the message menu.

When

7 BITS

or

14 BITS

are selected, the total number of
hexadecimal character of the message must be a multiple of 7
characters (28 bits).

I

Operation Reference

1

Function

Setting the Message

The message menu looks like the following:

MESSAGE NO.1

MESSAGE LENGTH 40

MESSAGE NO. is defined as the following where “X” represents the

phase setting:
0:

Arbitrary message set from the external controller using the
HP-IB capability. The data must be entered in units of words.
Refer to

the Buffer Memory for the Arbitrary Messages” in Chapter

START

FRAME and STOP FRAME are defined in the following

:PAGing

. . . ,

and “Using

2.

menu:

START FRAME

STOP FRAME 127

lb-12 Operation Reference

The frames between the START FRAME and STOP FRAME will be
transmitted. The allowable ranges for both are 000 to 127.

1: Displays: 0123456 [Xl

where “X” =

“3” for phase D.

2: Displays: ABCDEFG

3: Displays: TEST PAGING :XXXXXXX

where “XXXXXXX” = “PHASE A”, “PHASE B”, “PHASE C”, or

“PHASE D”.

4: Displays: ALPHANUMERIC 40CHARS TEST PAGING :XXXXXXX

where “XXXXXXX” = “PHASE A”, “PHASE B”, “PHASE C”, or

“PHASE

5: Displays: 8888888888888888888888888888888888888888

for phase A, “1” for phase B, “2” for phase C,

.

Function

for LCD test with 40 characters of “8”.

6:

User-definable message, up to 40 characters long, set from
the front panel. Enter numeric messages with the keypad.
Alphanumeric messages require the

(SHIFT) key
to access the alphabetical characters (blue letters) above
the keypad. If required alphabetical characters are not
available on the front panel, send a message from an external
controller over HP-IB. Refer to

:

n MESSAGE LENGTH specifies the maximum number of characters that

FLEX

:

string”’ in Chapter 2.

:

will be sent out and displayed in the message field. The allowable
range is 1 to 40. After specifying the number of characters, press

(ENTER) to save the new value.

When the value of this parameter is equal to or greater than the
length of the message, the whole message will be sent out.

When the value of this parameter is less than the length of the
message, only the characters specified by this parameter are output.
(For example, if the MESSAGE NO. is 1 (0123456[Xj) and the MESSAGE
LENGTH is 5, the message which is displayed and will be sent out is
actually 01234.)

Operation Reference lb-13

Function

Setting the Encoding Mode

The number of times a message is transmitted and the level of that
transmission are determined by the following menu:

MODE BURST
BURSTS 003

MODE determines whether the message will be output once or
multiple times when

SINGLE:
BURST:

CONT:

AMPLITUDE sets the output signal level of the carrier.

BURSTS sets the number of times the message will be transmitted.
This parameter is displayed only when the MODE parameter is set to

BURST. The allowable range is 1 to 256.

Outputs the message once.
Outputs the message the number of times specified
in the BURSTS field (3 times in this example).
Outputs the message continuously until the

(START/STOP) key is pressed a second
time. (Note: The collapse cycle described later
on in this section will determine how often the
message will be transmitted per cycle.)

(START/STOP) is pressed.

lb-14 Operation Reference

RF OFF is displayed below the amplitude setting when the RF output
is turned off. To toggle the RF signal output on and off, press

HOLD is displayed when the step attenuator is held at its current
range setting. To toggle the attenuator hold function on and off,
press

Function

Another menu is displayed as follows for completing the Encoding

Mode:

IMMEDIATE STOP OFF

HEADER ON

TERMINATOR ON

IMMEDIATE STOP terminates pager signaling as follows when a stop
event occurs.

Note

ON:
OFF:

Terminates pager signaling immediately.

Default setting. Terminates pager signaling just
before the next instance the pager is on.
(If TERMINATOR is set to ON, the pager encoder
generates the re-synchronization pattern in the
frame that was supposed to contain the message.)

HEADER sets whether the idle frame signal is output in the frame
before the first message.

ON:
OFF:

Default setting. Outputs the idle frame signal.
Does not output the idle frame signal.

TERMINATOR sets whether the re-synchronization pattern is output
after the last message. The collapse cycle will determine in which
frame the re-synchronization pattern appears after the

(START/STOP) key is pressed to stop or at the end of a burst

sequence (refer to “FLEX/FLEX-TD Signaling Examples”).
ON:

Default setting. Outputs the re-synchronization
pattern.

OFF:

Does not output the re-synchronization pattern.

If TERMINATOR is set to OFF, the pager under test is not asynchronized.
Therefore, the pager can not be synchronized with the future
page until the re-synchronization pattern is sent. To send the
re-synchronization pattern, set TERMINATOR to ON in this menu or
select RESYNC in the format menu.

Operation Reference lb-15

Function

Note

Entering the Pager

(Address)

The pager code menu looks like the following:

n PAGER CODE accepts alphanumeric characters up to 16 digits.

Use the numeric keys to enter the
alphabetical character, press

To select an

(SHIFT) before the numeric
key associated with the desired alphabetic character. Terminate
your entry with the

A FLEX/FLEX-TD pager’s
information. Entering the

(ENTER) key.

contains address and protocol

in the PAGER CODE data field
automatically sets up the ADDRESS TYPE, ADDRESSI, and ADDRESS2 in
the address menu, and the FRAME, PHASE, and COLLAPSE CYCLE in the
protocol menu as well.

The following table shows an example of the conversion from

to the parameters. Note that the values of COLLAPSE CYCLE

and FRAME are changed.

A0012477

n DUMMY CALL inserts a message with all 5s in all non-call phases. This

SHORT
SHORT
SHORT

0045245
0045245
0045245

None
None
None

011
011

127

COLLAPSE

D
D
D

4
2
2

is required by the FLEX-TD standard (RCR STD-43A) for sensitivity
testing.

ON:

Default setting. Activates the dummy call function
for equalizing the FSK deviation. An address for
the non-call phases must be set.

OFF:

Does not activates the dummy call function. Idle

frames are set in the non-call phases.

lb-16 Operation Reference

The address menu will display the following information:

n ADDRESS TYPE selects the address length.

Function

encode41 .Cdr

SHORT:
LONG:

Short address
Long address

ADDRESS1 is the 7-digit short address or the primary address of the

long address.

n ADDRESS2 is the 7-digit secondary address of the long address. (This

is displayed only when ADDRESS TYPE is set to LONG.)

If DUMMY CALL is ON, the following address menu is displayed.

ADDRESS TYPE

ADDRESS1 0032769

SHORT

ADDRESS TYPE (DUMMY CALL) displays the address type used in the

non-call phases (automatically set).
SHORT:

LONG:

Short address
Long address

Note

n ADDRESS1 is the 7-digit short address or the primary address of the

long address.

n ADDRESS2 is the 7-digit secondary address of the long address. (This

is displayed only when ADDRESS TYPE (DUMMY CALL) is LONG.)

To equalize the FSK deviation, the addresses for DUMMY CALL should

contain an equal number of “1” and “0”.

Operation Reference lb-17

Function

Setting the Protocol

The protocol menu displays the following information when

is the previously entered

I

I-

CYCLE 00

CYCLE 0

000

PHASE A
REPEAT 0

These parameters, except for CYCLE, are all automatically set when
the

n CYCLE: Defines the start cycle. The allowable range is 0 to 14.

is entered in the PAGER CODE data field:

FRAME: Defines the start frame where the message is located. The

allowable range is 0 to 127.

n PHASE: Defines the phase for the pager. The allowable range is A, B,

C, or D.

COLLAPSE CYCLE: Determines how many times a message repeats

within a cycle when BURST or CONT is active in the encoding MODE
setting. The default setting of 4 will repeat the message once every

16 frames

n REPEAT: Displayed only if FLEX-TD is selected in the format menu.

The allowable range is 0 through 7.

Defines the repetition transmission value. Determines how many
cycles the message will be repeated. The allowable range is 0 to 3.

1 b-l

Setting the Roaming Mode

Function

ROAMING MODE NONE

n ROAMING MODE determines the mode in which a pager is tested.

NONE:
SSID:

Tests a pager without the roaming mode.
Tests a pager in the SSID mode which responds to

a simulcast transmission system. SSID consists of
three words as follows:

q

SSIDl (BIWOOO):

Local Channel ID
Coverage Zone

•I
Country Code

Traffic Management Flag

q Frame Offset (BIWlOl)

SSID, NID:

Tests a pager in the SSID and NID modes. The NID
mode, in addition to the SSID mode, is a roaming
network for covering wider multiple areas. NID
consists of a network address and a short message
vector as follows:

•I SSIDl (BIWOOO):
Local (Channel) ID

Coverage Zone

q

SSID2

Country Code
SSID Traffic Management Flag (TMF)

q Frame Offset (BIWlOl)

q

NID

Network Address: 21 bits
Short Message Vector:

RF Channel (M)
Multiplier
(Service) Area
NID Traffic Management Flag (TMF)

Operation Reference

1 b-l 9

Function

Note

When ALPHANUMERIC is selected in the PAGER TYPE field and
SSID, NID is selected in the ROAMING MODE field, the maximum
allowable range of the MESSAGE LENGTH field is limited to 35.

The following menu is displayed for setting the SSID mode for a pager
to be tested:

n LOCAL ID: Defines the local channel ID of a pager under test. The

allowable range is 0 to 511.

n COVERAGE ZONE: Defines the coverage zone of a pager under test.

The allowable range is 0 to 3 1.

n COUNTRY CODE: Defines the country code. The allowable range is

0 to 1023.

n SSID TMF: Defines the SSID traffic management flag. This value is

automatically set when the

(address) is entered in the

PAGER CODE data field. The allowable range is 0 to 15.

After completing the previous menu, set FRAME OFFSET in the
following menu:

n FRAME OFFSET: Defines the number of frames to be offset by

range is 0 to 63.

lb-20 Operation Reference

Function

The next menu is displayed for setting the NID mode after completing

the SSID mode settings only if the SSID and NID modes are selected:

n ADDRESS: Defines the network address which appears on the RF

channel within the address field in predicted frames. The allowable
range is 2058240 to 2062335.

RF CH: Represents each RF channel obtained by the formula as

follows:
RF CH = Modulo 8 of Integer [(RF Freq. kHz)/(channel space
The allowable range is 0 to 7.

n AREA: Defines the service area identification. The allowable range is

0 to 31.

n MULTIPLIER: Defines how much the network address is extended.

The allowable range is 0 to 7.

n NID TMF: Defines NID traffic management flag. This value is

automatically set when the

(address) is entered in the

PAGER CODE data field. The allowable range is 0 to 15.

Operation Reference lb-21

Function

Message During Encoding

To start and stop encoding after selecting all pager encoder
parameters, press the

display is shown during encoding a pager under test:

(START/STOP) key. The following

Note

Note

REPEAT is displayed additionally only if FLEX-TD is selected in the

format menu.

If MESSAGE NO. is set to 0, the display is changed as follows:

If the RF output is turned off, AMPLITUDE x .
for RF OFF. While encoding, the blinking cursor is on the first
character A of AMPLITUDE or R of RF OFF.

will be substituted

1 b-22

Operation Reference

Function

Signaling Examples

The following examples illustrate the frame structure for the three
transmission repetition settings. The HEADER and TERMINATOR
parameters are set to ON (default), and the COLLAPSE CYCLE (CC) is
set to 1 and 2 (messages will be repeated every 2 frames (2l) and

4 frames

n SINGLE Mode Example

q Since HEADER is set to ON, the idle signal is output at Frame 126.
q With TERMINATOR set to ON, the asynchronous state signal is

output after the message.

respectively).

Start Cycle: 10
Start Frame:
Collapse Cycle: Has no effect

CC= 1 idle message asynchronous

127

n BURST Mode Example

Start Cycle: 10
Start Frame:
Collapse Cycle: 1 (2l) and 2
Burst:

q Since HEADER is set to ON, the idle signal is output at Frame 126.
q With TERMINATOR set to ON, the asynchronous state signal is

3

output in the frame where the next message was supposed to
occur (as determined by the collapse cycle).

11

Cycle 10
Frame 126

CC= 1 idle message idle message idle message idle

CC=2 idle message idle idle idle message idle

10

127 0

11

11

11

1

2

11

3

4

127

11

5

asyn-

chronous

idle

11 11

6 7

idle message

11
11

asyn-

chronous

Operation Reference

1 b-23

Function

n CONT Mode Example

Start Cycle: 10
Start Frame:

127
Collapse Cycle: 1 (2l) and 2
stop: Selected in frame f+ 1

Since HEADER is set to ON, the idle signal is output at Frame 126.
With TERMINATOR set to ON and IMMEDIATE STOP set to

OFF, selecting stop will replace the next message with the
asynchronous signal.

Cycle 10 10 11 11 11

0

1

2

message idle message idle

idle

CC=2 idle message

I I

idle

idle

idle . .

message idle

c

f+l

f

asyn-

chronous

idle idle asyn-

chronous

1 b-24

Operation Reference

Function

Roaming Example

When the roaming function with SSID and NID is set to on with the
following conditions, the contents in each phase are shown in the
following table:

n 6400 bps, 4-level FSK
n Call in Phase: A
n Address Type: Long Address

n Roaming Mode: SSID, NID

(for Network Address)

IB

Idle

1 BIW 101 System Messages: Time Instruction,

Seconds Adjust: 0,
Daylight Savings: No (Standard Time),
Local Time Zone: Greenwich Meridian

2 Vector Type: Short Message/Tone Only,

Message Type: 3 Numeric Characters (000) with Short Address

Idle Idle

where,
BI:

AF:
VF:
MF:
IB:

Block Information
Address Field
Vector Field
Message Field
Idle Block

Operation Reference

1 b-25

Function

If the firmware revision of the HP 8648A Option

is B.04.08 or

below, the contents in each phase are shown in the following table:

n 6400 bps, 4-level FSK

n Call in Phase: A
n Address Type: Long Address

Roaming Mode: SSID, NID

Dummy Address 2

block 2

where,

BI:
AF:

VF:
MF:

IB:

IB

Idle

Block Information
Address Field
Vector Field
Message Field
Idle Block

Dummy Message

Dummy Message

Idle

Dummy Message

Dummy Message

Idle

1 b-26

Operation Reference

POCSAG

Function

Setting the Data Rate and Pager Type

The parameter menu for the data rate and the pager type looks like

the following:

n

DATA RATE

512:

1200:

2400:

n

PAGER TYPE

NUMERIC:
TONE ONLY:
ALPHANUM 7BIT:

ALPHANUM 8BIT:

ALPHANUMERIC:

DATA RATE
PAGER TYPE

5 12

512 bps
1200 bps
2400 bps

Numeric type
Tone only type
7-bit coded alphanumeric type entered by
hex-binary code

hex-binary code
7-bit coded alphanumeric type

FUNCTION 00

Operation Reference lb-27

Function

Note

The ALPHANUM 7BIT and ALPHANUM 8BIT types can be used for
displaying two-byte special characters, for example Chinese
characters, through a conversion table.

The following examples show how the actual bit streams are
transmitted if

q

For ALPHANUM 8BIT

is set to the message (MESSAGE NO. 6):

First Byte Second Byte

MSB

LSB MSB

Bit number
Bit streams

Characters

q

For ALPHANUM

1011000010100001

B 0

A

1

The eighth bit (b8) is ignored as follows:

First Byte

MSB

LSB MSB

Second Byte

LSB

LSB

Bit number

b7 b6 b5 b4 b3 b2 bl

b7 b6 b5 b4 b3 b2 bl
Bit streams 01100000100001
Characters

(3)

0

1

When converting the binary data stream to 2-level FSK, the first bit
out becomes the least significant bit (LSB) of the 2-level symbol
with the following bit the most significant bit (MSB) of the symbol.

n FUNCTION determines the pager’s response depending on the pager

type. The allowable range is 00 to 11.

1 b-28

Operation Reference

Setting the Message

The message menu looks like the following:

Function

MESSAGE NO.1

n MESSAGE NO. is defined as the following where “X” represents the

MESSAGE LENGTH 40

phase setting:

0:

Arbitrary message set from the external controller using the
HP-IB capability. The data must be entered in units of words.
Refer to

:

<NRl>,

:

:

. . . ,

FLEX

and “Using

the Buffer Memory for the Arbitrary Messages” in Chapter 2.
This arbitrary message buffer is divided into multiple segments

by assigning START BATCH and STOP BATCH in the following
menu:

FREQUENCY

AMlJlUDE

I

The allowable ranges for both are 000 to 127.
Displays: 0123456

1:
2: Displays: ABCDEFG [PI
3: Displays: TEST PAGING: POCSAG
4: Displays: ALPHANUMERIC 40CHARS TEST PAGING : POCSAG
5: Displays: 8888888888888888888888888888888888888888

for LCD test with 40 characters of “8”.

6:

User-definable message, up to 40 characters long, set from
the front panel. Enter numeric messages with the keypad.
Alphanumeric messages require the

(SHIFT) key
to access the alphabetical characters (blue letters) above
the keypad. If required alphabetical characters are not
available on the front panel, send a message from an external

Operation Reference

1 b-29

I

Function

controller over HP-IB. Refer to

:

n MESSAGE LENGTH specifies the maximum number of characters that

I FLEX

: DEFine ‘string”’ in Chapter 2.

:

:

will be sent out and displayed in the message field. The allowable
range is 1 to 40. After specifying the number of characters, press

(ENTER) to save the new value.

When the value of this parameter is equal to or greater than the
length of the message, the whole message will be sent out.

When the value of this parameter is less than the length of the
message, only the characters specified by this parameter are output.
(For example, if the MESSAGE NO. is 1(0123456[-1) and the MESSAGE
LENGTH is 5, the message which is displayed and will be sent out is
actually 01234.)

lb-30 Operation Reference

Setting the Encoding Mode

Function

The number of times a message
transmission are determined by

I

I 1

I

FREQUENCY

MODE BURST
BURSTS003

is transmitted and the level of that
the following menu:

MODE determines whether the message will be output once or
multiple times when

SINGLE:
BURST:

Outputs the message once.
Outputs the message the number of times specified

(START/STOP) is pressed.

in the BURSTS field (3 times in this example).

CONT:

Outputs the message continuously until the

(START/STOP) key is pressed a second

AMPLITUDE sets the signal output level of the carrier.

BURSTS sets the number of times the message will be transmitted.

This parameter is displayed only when the MODE parameter is set to
BURST. The allowable range is 1 to 255.

RF OFF is displayed below the amplitude setting when the RF output

is turned off. To toggle the RF signal output on and off, press

HOLD is displayed when the step attenuator is held at its current
range setting. To toggle the attenuator hold function on and off,
press

Operation Reference lb-31

Function

Entering the Pager

(Address)

The pager code menu looks like the following:

PAGER CODE

n PAGER CODE accepts only numeric characters up to 7 digits.

Use the numeric keys to enter the
with the

(ENTER) key.

0000000

Terminate your entry

Message During Encoding

To start and stop encoding after selecting all pager encoder

parameters, press the
display is shown during encoding a pager under test.

(START/STOP) key. The following

Note

MESSAGE NO. 6

If the RF output is turned off, AMPLITUDE x .

AMPLITUDE O.OdBm

will be substituted
for RF OFF. While encoding, the blinking cursor is on the first
character A of AMPLITUDE or R of RF OFF.

1 b-32

Operation Reference

RESYNC

Function

Setting the Encoding Mode

The following parameters must be set to activate the
resynchronization function for a FLEX/FLEX-TD pager under test:

BURSTS 001 AMPLITUDE

n BURSTS defines the number of data to make a pager

I

with this pager encoding signal. One burst is 1.92 s. The allowable
range is 000 to 256. 0 represents the continuous mode.

Note

This setting is required only when RESYNC is selected in the format
menu. The

(PREV) and

(NEXT) keys toggle the format menu

and this BURSTS menu. No other menus are displayed.

Message During

To start and stop encoding after selecting all pager encoder
parameters, press the

RESYNC SENDING

I

I

(START/STOP) key.

I

Note

If the RF output is turned off, AMPLITUDE x .

will be substituted

for RF OFF. While encoding, the blinking cursor is on the first
character A of AMPLITUDE or R of RF OFF.

Operation Reference

1 b-33

Function

PN15

Setting the Data Rate

If PNl5 modulation is selected in the format menu, the following
parameters must be set to complete the pager encoder setup process.

DATA RATE

512 bps, 2-level FSK

1200 bps, 2-level FSK

1600 bps, 2-level FSK
2400 bps, 2-level FSK
3200 bps, 2-level FSK
3200 bps, 4-level FSK
6400 bps, 4-level FSK

Note

Note

This setting is required only when PNl5 is selected in the format
menu. The

(PREV) and

(NEXT) keys toggle the format menu

and this PN15 FSK data rate menu. No other menus are displayed.

Message During Encoding

To start and stop encoding, press the

PN15 SENDING

If the RF output is turned off, AMPLITUDE x .
for RF OFF. While encoding, the blinking cursor is on the first
character A of AMPLITUDE or R of RF OFF.

(START/STOP) key.

AMPLITUDE

encode31

will be substituted

1 b-34

Operation Reference

Function

SERVICE

This function is used for servicing the HP 8648A Option lEP, and
provides a continuous FSK signal.

Setting the Data Rate

The following parameter must be set to activate the service function:

n CALIBRATION FSK is one of the data rates as follows:

512 bps, 2-level FSK
1200 bps, 2-level FSK
1600 bps, 2-level FSK
2400 bps, 2-level FSK
3200 bps, 2-level FSK
3200 bps, 4-level FSK
6400 bps, 4-level FSK

Note

Note

This setting is required only when SERVICE is selected in the format
menu. The

(PREV) and

(NEXT) keys toggle the blinking cursor
between the format parameter and this CALIBRATION FSK parameter.
No other menus are displayed.

Message During Servicing

To start and stop encoding, press the

If the RF output is turned off, AMPLITUDE x.
for RF OFF. While encoding, the blinking cursor is on the first
character A of AMPLITUDE or R of RF OFF.

(START/STOP) key.

will be substituted

Operation Reference

1 b-35

Pulse Modulation

Pulse Modulation

Note

1. PULSE

Pulse modulation is valid only for instruments with Option

To select pulse modulation, press (AM) (PULSE) twice. If RF is on, the

display will look like the following representation. The

ON/OFF]

key enables or disables the pulse modulator.

Note

When the instrument is in the pulse modulation mode, pulse
modulation should be turned off using

ON/OFF) before switching

off the instrument. If the instrument is switched off while the pulse
modulation mode is turned on, the instrument will power up with no
RF output.

PULSE MOD

PULSE MOD

OF’F

The word PULSE is shown in the AMPLITUDE portion of the display

when pulse modulation is enabled ([MOD ON/OFF]) and the RF is
turned on

In this case, no RF will be present at the RF
output unless a TTL-high signal is applied to the rear-panel PULSE IN
connector.

1 b-36

Operation Reference

Pulse Modulation

The following keys are invalid when the pulse modulation screen is
visible:

n

n

n @EC--

D

n

Operation Reference lb-37

Increment Set

Increment Set

1. INCR SET

Note

Note

Press

to view or change the increment set value for the

currently active function (the active function is the last function key

you press;

press

0 is displayed between the value and the units. The

indicates that the displayed value is the increment set value.
An increment value cannot be set for the knobs or the memory recall

arrow keys.

Set Ranges

Function

Range

1 Hz to 999.75 MHz

FM Deviation
AM Denth

> 0.0 to 149.0
> 0.0 to 150.5
> 0.0 to 100 kHz
> 0.0 to 100%

(HP 8648A)

(HP

0.01 to 1.0 kHz

It is possible to set an increment value of greater resolution than can
be displayed or than the hardware can respond to. However, the
instrument records each arrow key press and will respond after the

appropriate number of presses.

1 b-38

Operation Reference

START/STOP Encoding

If Option
mode, the

is present and the signal generator is in the ENCODER

key functions as a START/STOP key to start or

stop the pager encoding when in the pager encoder mode.

PREV and NEXT

If Option
mode, the

is present and the signal generator is in the ENCODER

and

keys function as the PREV and NEXT keys to
change the blinking first character between each parameter when in
the pager encoder mode.

Data

Data

\

1. MHz/dBm

Note

Press a units key after you enter a value. This terminates the entry.

Note that the units keys in the left column are each labeled with an
amplitude unit on the bottom and a frequency or modulation unit on
the top. The instrument applies the appropriate unit for the function
value you are entering. The bottom key in the row for instance,
terminates a

Memory register selections, sequence selections, and HP-IB address
entries do not require a units key to terminate the entry. These
entries are automatically terminated after the last digit is entered.

entry in radians or an amplitude entry in

Units Conversion

You can change the units of the displayed frequency or amplitude
value by selecting the FUNCTION (frequency or amplitude) and then
pressing a units key. The instrument will convert the displayed value
to the equivalent value for the units key you pressed.

ENTER

If Option 1EP is present and the signal generator is in the ENCODER
mode, the
key must be used to store any numeric or alphabetic characters
entered by way of the DATA and MODULATION source blocks.

key functions as an ENTER key. The ENTER

If Option 1EP is present and the signal generator is in the ENCODER
mode, the
input alphabetical characters using the DATA and MODULATION
SOURCE blocks when in the pager encoder mode.

key functions as a SHIFT key. This key lets you

Operation Reference lb-39

2. Backspace

Press
the last digit entered.

when entering a numeric value to backspace and remove

3. emf

4.

Press these keys to display the amplitude value indicated on the key
label in electromotive force units. Emf is the RF output voltage with
no load. It is twice the output voltage with a 50 ohm load.

Press this key at any time while you are entering an amplitude or
reference offset value to change the sign of the value.

1 b-40

Operation Reference

Instrument Preset

Instrument Preset

(POWER)

Note

Turn the instrument on while pressing the backspace key
perform an instrument preset. The instrument will power up to
factory-defined settings shown in the following table. Save and recall
registers are not affected by this operation.

Turn the instrument on while pressing the memory
perform a clear memory. This function erases all save/recall registers,
sets the HP-IB address to 19, and performs an instrument preset
where the instrument powers up to factory-defined settings shown in
the following table.

This will cause an error message to appear on the display:
627 Battery RAM failure

: memory lost.

This is normal.

to

key to

Operation Reference lb-41